Adapter pattern in javascript using data munging example.

adapter-pattern-munging-data.example.js

const v1Data = {
  metrics: {
    weightLb: 400,
    heightFt: 6
  },
  macros: {
    gramsFat: 1000
  }
};

const v2Data = [400, 6, 1000];

function fetchData() {
  return axios.get(url);
}

function v1Adapter(data) {
  return {
    weightLb: data.metrics.weightLb,
    heightFt: data.metrics.heightFt,
    gramsFat: data.macros.gramsFat
  };
}

function v2Adapter(data) {
  return {
    weightLb: data[0],
    heightFt: data[1],
    gramsFat: data[2]
  };
}

function saveDataOrAnythingElse(data) {
  this.setState({ d: adapter(data) });
}

// save data with v1 format
fetchData()
  .then(v1Adapter)
  .then(saveDataOrAnythingElse);

// save data with v2 format
fetchData()
  .then(v2Adapter)
  .then(saveDataOrAnythingElse);

// The final output should always be the format:
// { weightLb, heightFt, gramsFat; }
// if we need to change the format, or the api return changes,
// then we only need to create a new adapter and plug that in. One thing to test
// and well separated from the rest of the code.